1. Field of the Invention
The invention relates to an ingot mould for continuous casting, comprising: wide side plates, one of which forms a fixed side wall and the other a loose side; adjustable narrow side plates, which can be clamped by the wide side plates; and adjusting cylinders adjustable to a supporting force for the wide side plate forming the loose side wall.
2. Discussion of Prior Art
Various constructions of ingot moulds of the kind specified are known. In such moulds as a rule both narrow side plates can be adjusted by means of adjusting members, more particularly by hydraulic adjusting cylinders; while one of the wide side plates is fixed in a given position in a frame by adjustable supporting elements, for example, adjusting screws, and thereby forms a fixed side wall, the other wide side plate can be adjusted via adjusting members, more particularly hydraulic adjusting cylinders and therefore forms a loose side wall. During the pouring operation, the clamping force of the wide side plate acted upon by the hydraulic adjusting cylinders clamps the narrow side plate positively in the required position between the wide side plates. The advantage of the wide sides being supported on adjusting cylinders is that the supporting force can be adjusted. When the supporting force is exceeded by the strand forming in the mould, the wide side can yield (European Pat. No. 0 107 546 B1; German Pat. No. 32 35 673 A1).
The pressurizing of the wide side plate adjusting cylinders is of decisive importance for the mould to retain its format, since if pressure drops, the clamping is lost, so that the plates yield to the pressure in the mould and move away.
An ingot mould is also known in which the wide side plates are adjusted by means of adjusting screws. To provide the clamping force for the narrow side plate, the wide side plates bear via packs of cup springs against the adjusting screws. Hydraulic tensioning cylinders tension the packs of cup springs. The hydraulic tensioning cylinders are inoperative during the pouring operation. Then the wide side plates bear via prestressed packs of cup springs against the adjusting screws acting as rigid abutments. It is true that that mould avoids the risk run by other moulds that the clamping force is lost if the pressure medium fails, but due to the pack of cup springs, the adjusting screws and the tensioning cylinders, the mould is an expensive construction (German No. OS 27 42 742).
Finally, an ingot mould is known in which hydraulic adjusting cylinders are provided to adjust the narrow side plates. Parallel with the hydraulic adjusting cylinders, guide spars which can be fixed in hydraulically operated clamping bushes ae connected to the narrow sides. Clamping bushes are activated when the adjusting cylinder has moved the associated narrow side plate into the required position (German Pat. No. 26 20 751 A1).